1. Field:
This invention relates generally to apparatus which remove liquids from wet solid masses by application of mechanical pressure.
2. State of the Art:
There are at present several methods by which the liquid and solid fractions or phases of a wet mixture can be separated to yield a cake. These include vacuum filtration, pressure filtration, centrifugation and compression in, for example, the so-called belt presses.
Any of these methods will yield a cake that, although appearing dry, may still contain more than fifty percent moisture by weight. In situations in which the cake must be further dewatered, removal of more of the remaining liquid phase is typically carried out by heating, which of course significantly adds to the overall operating expense, especially in view of the current high energy costs. For these reasons, it is apparent an improved apparatus which would mechanically remove sufficient liquid phase from the wet mixture to avoid such additional steps would be desirable, not only from the viewpoint of managing the costs of the liquid-solid separation, but also from the broader perspective of conserving scarce energy resources.
An effective apparatus for deliquefying a mass of wet solid particles is disclosed in U.S. Pat. No. 4,475,453. The satellite rolls and primary roll of the apparatus have a resilient rubber-like covering which extends the nips existing between the satellite rolls and the primary roll.